Suitability of a Laser dinghy for learning
I am not against the idea of tearing across the bay at a high rate of knots,
But the thing with a one design racer like a laser is not that you tear across at a high rate of knots, it is that you tear across at a highER rate of knots THEN ALL THE OTHER LASERS. If one of the little skiffs happened to be in the area, it would pass you by at about three to five times the speed of the fastest laser. See, just because a laser is a race boat does not mean it is built for ultimate speed. It is actually built for repetitive cosistency across the whole class, so that everyone has more or less the same boat (with some tolerable variation based on how much money you want to spend on a pair of blocks the size of a ten cent coin and such)...that way the sport is about a test of the sailor and his tactics and choices on the day, rather then who has the fastest hull.
I have to admit, you may end up looking at boats on a case by case basis for a while to see what is available. You basically want something with a bit more beam then a laser and a lot more freeboard. A comfortable internal layout and likely the ability to use a headsail as well as a main. The first step up form a laser in thsi direction would be a Pacer...but really, they are not all that comfy either (but you can dig up lots of pics on the net to see the general direction I am trying to advise you in).
I guess what it comes down to is, stop thinking in terms of open-wheeler race car and start thinking towards "Swollows And Amazons" type dinghies. Only in fibreglass, more modern and low maintenance setups.
This site may be of some help to you in showing pics and characteristics of common dinghy designs.
If you step outside the one design racers, you will also be more likely to find a bargain as someone moves up to a big boat rather then tries to finance a yet more space-age-materials laser upgrade to get an extra .04knots around the markers.